A young punk-rock teenage girl from Japan who was up to no good until April O' Neil and the turtles showed her that life could be better. She became April's sidekick for the spinoff-comic "April O' Neil" in which Chien Khan returns to his former glory in a battle with a demon who also took control of a large group of Ninja.

Created by Dean Clarrain and Chris Allan for the TMNT Adventures comics, a young punk-rock teenage girl from Japan who was up to no good until April O' Neil and the turtles showed her that life could be better. She became April's sidekick for the spinoff-comic "April O' Neil" in which Chien Khan returns to his former glory in a battle with a demon who also took control of a large group of Ninja.
Oyuki first met April and the turtles in the Rising Sun arc, where Oyuki was kidnapped and set to be sacrificed by criminal Chien Khan in order to release the demon called Noi Tai Dar. After being rescued by the turtles and their allies, she is offered a home by April.
In New York, circumstances force April to work as a freelance reporter, with Oyuki as her camera-girl. In reporting, Oyuki found her calling; in the story titled The Angel of Times Square, set in 1999 (five years in the future—the series is normally set in 1994) it is revealed that Oyuki eventually became a reporter in her own right, and that she still lived with April.